In recent years, flash memories have become lower in price, and a high-speed flash drive (e.g., solid state drives (SSD)) including flash memory is installed in storage systems as well. Since the performance of the flash drive is high in such a storage apparatus, there is a problem that a microprocessor (MP) included in a controller of the storage apparatus becomes a bottleneck and the resource of a flash device cannot be utilized sufficiently.
In this regard, a technique in which a flash drive is shared and used by a plurality of storage apparatuses has been devised. In this technique, one of the purposes is to render data movement unnecessary even in the case of migration from an existing storage apparatus to a new-generation storage apparatus.
However, this technique assumes that the physical format (block size) or the format of a data guarantee code or the like is the same for data handled by a storage apparatus before migration and a storage apparatus after migration, and cannot be applied to migration between storage apparatuses that handle different formats.
In recent years, there are cases where the format of a data guarantee code of data handled by a storage apparatus is changed in order to improve reliability. Hard disk drive (HDD) formed of 4 KB sectors (blocks) have also appeared, and it is presumed that changes or the like of a format from 512 byte to 4 KB blocks will occur in the future. Thus, there may be a possibility of migrations between storage apparatuses of different formats occurring frequently.
Meanwhile, a technique is known in which attribute information (sector size or the like) of a migration-destination storage apparatus is acquired and data is migrated to the migration-destination storage apparatus after changing the format based on the attribute information (e.g., see PTL 1).